I would like to draw custom images within a ListView, for this I have created a ListView and an ArrayAdapter object. I have specified that each element of the ListView will be an ImageView which is specified by an XML layout file. Now, I would like to draw a custom graphic in each cell depending upon certain paramters.
View 3 Replies
When I try extending the View class to a subclass that will underline portions of the text drawn by ListView, the code compiles okay but results in a runtime exception apparently due to an improper class cast. Does anyone see what I've done wrong or have suggestions about getting access to the Canvas of ListView items so portions of text can be underlined?
Here is the code, which is the Efficient Adapter View/List example from ApiDemos with an added UnderlinedView class.
CODE:........
I have a few doubts about view flipper I am using viewflipper to go to another view using scroll_left animation. i have kept 2 linearlayouts inside the ViewFlipper Code...
View 2 Replies View RelatedI'm trying to draw a custom border by drawing a custom view. Here is a sample of one side of the border: Code...
View 1 Replies View RelatedI created a custom OverlayItem class so that I could essentially have one kind of OverlayItem whose Drawable marker would set itself depending on the state of some data that I pass into it. I have attempted to accomplish this by, on my first attempt, utilizing the setMarker method within the OverlayItem class. Once that did not work I attempt to override the getMarker method and have it return the appropriate marker to represent the data. Both of these attempts ended with nothing being drawn on the map...however if they are commented out the markers draw just fine (except they of course use the default marker, which isn't what I want). Here is my code for my custom OverlayItem class (the commented out methods I have tried and they have not worked):
private class MyOverlayItem extends OverlayItem {
private Context mContext; private MyData mData;
public MyOverlayItem(GeoPoint point, MyData data, Context context) {
super(point, data.getWhat(), data.getWhere()); this.mContext = context; this.mData = data;
/*if(data.getTemp() > 200) this.setMarker(res.getDrawable(R.drawable.icon_data_hot_l));
else if(data.getTemp() > 100) this.setMarker(res.getDrawable(R.drawable.icon_data_neutral_l));
else this.setMarker(res.getDrawable(R.drawable.icon_data_frozen_l));*/ }
/*@Override public Drawable getMarker(int stateBitset) {
Resources res = this.mContext.getResources(); if(this.mData.getTemp() > 200)
return res.getDrawable(R.drawable.icon_data_hot_l); else if(this.mData.getTemp() > 100)
return res.getDrawable(R.drawable.icon_data_neutral_l);
return res.getDrawable(R.drawable.icon_data_frozen_l);
}*/ }
Is there a way to do what I am attempting to do or do I need to make a unique OverlayItem class corresponding to each state of my data?
I have made a custom widget, very similar to JTable in Swing. It is not editable, and all data is replaced at once, allowing easy checking for the widest item in each column & custom col sizing at replace time. It is a subclass of LinearLayout, filled with re-usable TableRow Objects, sub-classed directly from View.
TableRow is both Clickable, focusable, & focusable In Touch Mode. TableRow overrides onDraw(Canvas), calling super. It draws the first column in Black with Lt gray underneath. If the TableRow isFocused () , then a filled rectangle is drawn, before the rest of the cols (left or right justified based on data type), and borders. Where do I get the color, orange, to draw the filled rectangle indicating focus? android.R.drawable.list_selector_background seems to be a pointer, value 17301602, not an actual color. Placing any real Color in my code draws things fine. Is this 17301602 transparent or something? Am I doing this wrong, or do I just need to know how to fine the orange?
I have a linear layout that I have overridden because I want to > dynamically add other views to it. I am trying to add some textviews > to it and I call addViewToLayout in the onLayout method. Can't you just add your views to the layout using addView()? I have one custom LinearLayout and this is what I do and it works fine. No need to override onLayout() or onDraw(). Maybe try that
View 10 Replies View RelatedI am working on something that needed custom drag-and-drop functionality, so I have been subclassing View, doing a bunch of math in response to touch events, and then rendering everything manually through code on the canvas in onDraw. Now, the more functionality I add, the more the code is growing out of control and I find myself writing a ton more code than I would expect to write in a high level environment like Android.
Is this how it's done, or am I missing something? If I'm not doing anything fancy in the UI, the framework handles the majority of my interactions. Built-in controls handle the touches and drags, and my code is pretty much limited to business logic and data. Is there a way to leverage the power of some of the UI controls and things like animations while also doing some of it manually in the onDraw canvas? Is there an accepted standard of when to use one or the other (if indeed the two approaches can be mixed)?
I am drawing text in my custom view in android using canvas.drawtext. i need to change back color, and want text right aligned. for example i want to print the text in a 10, 10, 100, 20 rectangle of color yellow and text color red and right aligned. how can i do that ?
View 2 Replies View RelatedI would like to change text and back ground color of my Listview without building custom rows. Is this possible ?
View 1 Replies View RelatedI have seen examples implementing a custom Filter. The Android developer docs talk about implementing a Filterable interface. Does anyone have any advice and/or sample code on the best way to implement filtering in a ListView ?
View 2 Replies View RelatedI am new to android. i want to add images in a ListView like below shown links.
View 3 Replies View RelatedI am wondering if which of the two is better in loading images in a listview from web, is it by batch through some number of threads that are running simultaneously or one by one through thread queue? I have noticed (but I don't know if that is really the implementation) from the youtube app that the images are loaded by batch and it is kinda fast. Even for not only loading images but also requesting some data from the web as well. Does anyone have an idea?
View 3 Replies View RelatedAndroid: How to display images from the web in a ListView? I have the following code to display image from a URL in an ImageView:
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import android.app.ListActivity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.widget.ImageView;
public class HttpImgDownload extends ListActivity {
/** Called when the activity is first created. */
@Override public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState); setContentView(R.layout.main);
Bitmap bitmap = // DownloadImage(
// "http://www.streetcar.org/mim/cable/images/cable-01.jpg");
DownloadImage( "http://s.twimg.com/a/1258674567/images/default_profile_3_normal.png");
ImageView img = (ImageView) findViewById(R.id.img); img.setImageBitmap(bitmap);
} private InputStream OpenHttpConnection(String urlString) throws IOException
{ InputStream in = null; int response = -1;
URL url = new URL(urlString); URLConnection conn = url.openConnection();
if (!(conn instanceof HttpURLConnection)) throw new IOException("Not an HTTP connection");
try{ HttpURLConnection httpConn = (HttpURLConnection) conn;
httpConn.setAllowUserInteraction(false); httpConn.setInstanceFollowRedirects(true);
httpConn.setRequestMethod("GET"); httpConn.connect();
response = httpConn.getResponseCode();
if (response == HttpURLConnection.HTTP_OK) { in = httpConn.getInputStream();
} } catch (Exception ex) { throw new IOException("Error connecting");
} return in; } private Bitmap DownloadImage(String URL) {
Bitmap bitmap = null; InputStream in = null;
try { in = OpenHttpConnection(URL);
bitmap = BitmapFactory.decodeStream(in);
in.close(); } catch (IOException e1) {
// TODO Auto-generated catch block e1.printStackTrace();
} return bitmap; } }
Now how can I display images in an array in a listview? Here's how I want to display the images:
http://sites.google.com/site/androideyecontact/_/rsrc/1238086823282/Home/android-eye-contact-lite/eye_contact-list_view_3.png?height=420&width=279
I'd like to create a list with an image on the right side of each entry - and preferably have a separate callback if the image is clicked.
much like the contact call-listview - can click on either the name (edit) or the phone icon on the right (call).
just wondering what kind of list and/or adapter i have to use.
i am quite new to android and i was wondering how i could go about adding a listview with different images and text. What i am trying to achieve is a listview with four rows which have a different Icon? I don't know how to set that up using the xml layout provided. should i build this using different multiple linear layout or is there a better way to go about it?.. All the examples i have seen all seem to be using one particular Icon and no much detail of the xml layout.
View 1 Replies View RelatedI try to implements lazy loading of images in a listview. There is no android features to make this, so I should implement it by myself. Have anyone already done this? Take the solution care of scrolling and lazy loading new images and stop to load not more necessary images?
View 3 Replies View RelatedI trying a hand at ListViews and my current experiment is aimed at displaying some data in a ListView. The data to be displayed in each row is simple: an image and some text. The images come from a remote server and the textual data is hardcoded. I have a class that downloads images using AsyncTask and caches the list of images fetched as SoftReferences in a LinkedHashMap. I am also passing a reference of the view to this class, so when the image download/cache read is complete the class will set appropriate Bitmap in the view.
Code...
I implemented the lazy-loading images in my ListView. I use a AsyncTask to download the image from the internet and bind it to the ImageView in the UIThread. It's working except that when I scroll the ListView vary fast, the downloaded images sometimes are binded into the wrong items in the list.I guess the problem is from the reuse of convertView in the BaseAdapter. Code...
View 2 Replies View RelatedHere are 4 references that I have found for lazy-loading images into a listview in Android. The idea is to display a placeholder image, get the actual image in the background, update the ImageView in the list when the image is available. I've tried to do this in the simplest way possible using an AsyncTask in an Adapter. The outline of that approach is below. Is it flawed? Is there an agreed approach to handling this common task? Code...
View 2 Replies View RelatedI've got the below screen that contains some images (6 per visible page). Scrolling up and down seems quite laggy to me. It's like it's rendering the images again. Scrolling back up seems worse than scrolling down.
Anyone know how to increase performance in such an area to create a nice smooth scroll?
Update: The images and text is all retrieved from my SQLite database. The list is created using SimpleCursorAdapter.
CODE:.......................
I have an array of all the URIs of the images which I am showing in a List. Now I want to run a thread in background which gets this images from web and store them on the SD card. So when I click a particular element in the list instead of fetching from web it should fetch from the SD card in the new activity.
View 3 Replies View RelatedI am using a custom adapter for my ListView as per the efficient adapter sample by Romain Guy. In the getView() method of my adapter I am assigning an ImageView a jpg image stored on SD using the following code...
View 2 Replies View RelatedThis is a very common scenario: displaying images in a ListView which have to be downloaded from the internet.Right now I have a custom subclass of ArrayAdapter which I use for the ListView. In my getView() implementation of the ArrayAdapter, I spawn a separate thread to load an image. After the loading is done, it looks up the appropriate ImageView and sets the image with ImageView.setImageDrawable(). So the solution I used is kind of similar to this one: http://stackoverflow.com/questions/541966/android-how-do-i-do-a-lazy-load-of-images-in-listviewThe problem I'm having is that as soon as I make the call to setImageDrawable() on the ImageView, the ListView somehow refreshes all currently visible rows in the list! This results in kind of an infinite loop. Code...
View 2 Replies View RelatedI have listview with items that include both text and images. If I scroll the listview fast enough all items images are messed up: wrong images are displayed for wrong items. The same problem exists with expandable listview. I tried to implement holder class to cache imageview and image itself using setTag, getTag but nothing helps. The faster I scroll the more items are messed up. Text almost always displayed correctly.
View 5 Replies View RelatedI populate a ListView from the result of a Sqlite query; one of the fields is the image file name that i would like to show as image into a listview.
How can i do to show the image file?
I use
SimpleCursorAdapter(this, R.layout.list_name,cur,new String[] {"fields_list"}, new int[] { R.id.list...});
In my case i would be retrieving values from sqlite database and have to display it in a list view...So how should i pass the images out from the database into the list view.. I am able to save and retrieve images individually and display it on the screen.But how do i pass a bitmap and display it in a list view.can you help me with some sample codes please...
View 1 Replies View RelatedI have several images present in different folders in my sdcard. I would like to display a list of thumbnails. So what I have done is while rendering any row in the list I read the file in an input stream, get the byte array, decode it to obtain a bitmap and set it in an imageview.
So far so good. But when I scroll the list, the list scrolls in jerks. I believe this is because decoding a bitmap from byte array takes some time. What I would like to know is that, is there any optimization which I can do to improve the performance, or better still is there any better method to achieve what I want ?
I am building a android aplication which will be consuming a json file from the internet. This json file contains a list of news from a particular website. Each json object contains information such like title, summary, descripition and web links for the news thumbnail and the original image.
I will be displaying in a listview three information: the news thumbnail, the title and the summary. Here resides my problem. I dont want to load all thumbnails from the internet if they wont be displayed. What I am trying to say is that why download a thumbnail from the 30th news if the user wont scroll down the image. So, i will, initially only download the thumnails from those news that are being displayed in the screen and when the user scrolls down to see more news, as soon as the list item appers to the screen i want to download the image and then display.
Is there a way to achieve this? Is it possible to find out if the list item is on the screen? I have been searching all over the internet for a solution for this but i am running out of ideas.
How can I create custom android virtual device, using my own images? I've been trying to change default *.img-s on my own in sdkplatformsandroidimages but it didn't help - the emulator didn't launch or frozen.
View 1 Replies View Related