Android :: Why Drawing In View Not Take Effect?
Mar 31, 2009
I'm trying to create a custom widget which looks lick HTML table. I chose to derive from TableLayout, which is the subclass of ViewGroup and View. What's confusing me is that the drawing I put into my override of View.onDraw did not take effect, until I moved the codes to the override of ViewGroup.dispatchDraw. I know dispatchDraw is a good place to draw something, but I'm just wondering why there's such difference in my practice?
View 3 Replies
Apr 21, 2010
How would I extend TextView to allow the drawing of text with a gradient effect?
View 2 Replies
View Related
May 26, 2010
I'm having a small problem with drawing a View offscreen to a Bitmap. The View is created using LayoutInflater.inflate(int resource, ViewGroup root) with null passed to the root parameter. The View has a fixed size (200x180 pixels). I can create a Bitmap for this View either by using the method View.getDrawingCache() or by calling View.draw(Canvas canvas) using a Canvas that in turn has a backing Bitmap. This works fine if the View doesn't change after the inflate. However, if I have a TextView inside my View that I will update, the size of the TextView is never updated regardless of what method I call on the View (requestLayout(), forceLayout() invalidate() etc.). If I display the View on screen directly, everything works fine (sizes are updated as needed, etc.). What is the correct way of drawing Views off screen and being able to update their layout when needed?
View 3 Replies
View Related
Jul 13, 2010
I am trying to put a background image and draw on top of that screen. I assumed activity will have a on draw method, but it does not have. it seems i need to use surfaceview. Can I put a surfaceview on top of the image view and make it transparent ? any example/tutorial i can refer to ?
View 5 Replies
View Related
May 4, 2009
Can you please tell me how does android determine when View should enable the drawing cache? I try calling in my class (which inherits form LinearLayout) Bitmap drawingCache = getDrawingCache(); I get a null in my drawingCache.
View 5 Replies
View Related
Aug 30, 2010
I'm trying to create the simplest 2D drawing program possible to isolate what exactly I can't figure out about drawing. This program should literally just draw a 20x20 rectangle. Here's what I have: Code...
View 1 Replies
View Related
Sep 9, 2010
I am using SurfaceView to draw my game on the screen of the phone. Basically now I want to be able to draw Android Views on my View, such as a Button or ListView. I am simlpy getting a Canvas and then I draw on that... does anybody know how to draw AndroidViews (Button, ListView.) on my Canvas?
View 2 Replies
View Related
Jul 6, 2010
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 Related
Sep 26, 2010
I'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 Related
May 1, 2009
I am a newbie in android UI programming. I want to create a custom SurfaceView for my own renderer. And this view has a transparent/ translucent effect with background. I follow api demo sample code to create TranslucentGLSurfaceViewActivity and TranslucentGLSurfaceView, but render result is blank screen.
View 3 Replies
View Related
May 12, 2010
I'm working with Android 2.1 and have the following problem:
Using the method View.getDrawingCache() always returns null. getDrawingCache() should return a Bitmap, which is the presentation of View's content.
Example code:
public void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final View view = findViewById(R.id.ImageView01);
view.setDrawingCacheEnabled(true);
view.buildDrawingCache();
final Bitmap bmp = view.getDrawingCache();
System.out.println(bmp);
}
I've already tried different ways to configure the View object for generating the drawing cache (e.g. View.setWillNotDraw(boolean) and View.setWillNotCacheDrawing(boolean)), but nothing works. What is the right way, or what I'm doing wrong? In real code I want to apply getDrawingCache() on a ViewGroup like RelativeLayout. Is the behaviour the same when using a ViewGroup?
View 2 Replies
View Related
Jul 19, 2010
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 Related
Aug 23, 2010
I have made a sample application to flip through different layouts in a viewflipper.
XML is basically (pseudo-code)
<ViewFlipper>
<LinearLayout><TextView text:"this is the first page" /></LinearLayout>
<LinearLayout><TextView text:"this is the second page" /></LinearLayout>
<LinearLayout><TextView text:"this is the third page" /></LinearLayout>
</ViewFlipper>...........
View 1 Replies
View Related
Jul 21, 2010
What is your best drawing app?
I've tried Draw!, Draw(er), and MagicMarker, but I dunno, they each have their pros and cons and can't find one that suits me well. I'm not looking for Photoshop on my phone, but something better than a colored line. So what is your best drawing app?
View 3 Replies
View Related
Aug 2, 2010
I am trying to set up a ViewFlipper that changes a SlidingDrawers content each time a button is pressed. So far every view I set up worked fine, but now I am trying to create a ListView (including single_choice_mode) within a child view of the ViewFlipper, but my attempt only let to a NullPointerException. As I only discovered ViewFlipper today, I am not yet familiar with it and may not have understood it completely. if someone could give me a hand and help me find out what I have done wrong, that would be great. Here is what I have done:
The code for the onClick event of the ImageButtons:
public void onClick(View v){
if (v == btnExposure){
mFlipper.setDisplayedChild(0); }
else if (v == btnProperties){
mFlipper.setDisplayedChild(1);}
else if (v == btnSpecialEffects){
mFlipper.setDisplayedChild(2);.............
View 1 Replies
View Related
Nov 5, 2010
This is more of a question about animating than a specific problem coding. i need to fill in the broad strokes left by the research i've been doing.
What i'm trying to do:
The activity should load with only the a togglebutton visible. when the button is touched, a png will be animated to a certain position relative to the togglebutton. also, another button will slide in from off screen and slide off if/when the togglebutton is pressed again.
What i can't figure out:
I can draw an image, but only via xml. creating an imageview and setting the background programmatically does nothing.
When i draw from xml, i can't move the image when the togglebutton is pressed like i want to. when i call getPositionOnScreen() i get a null pointer, even though the complier can see i'm referring to the imageview described in both xml and in code.
I'm calling getPositionOnScreen because via xml, i have the image positioned behind the togglebutton so that it's not visible until the button has been pressed and the image starts moving. the idea is that with different screen sizes i won't know exactly where the view is until runtime. getPostionOnScreen allows me to get the coordinates of the imageview so i know where it has been positioned. when i have a start position, can tell it to "move up" on the screen from behind the togglebutton by simply adding to x or y until it's where i want.
This is the code to draw the image (inserted in the onCreate method).
CODE:.......
This is the code i'm using to animate. when the button is clicked, it calls this method on the view from the listener.
CODE:...............
I'm well aware that this is horribly wrong and won't work. what i need to understand is why.
View 1 Replies
View Related
Apr 18, 2010
I'm trying to learn about Android programming by rewriting a C app I've moved from DOS to X-windows to Windows as a learning tool. It's just a silly little app that draws symmetrical 'game of life' patterns on the screen in a kaleidoscopic fashion. It's structured so that the patterns do their own animations. I.e. there's a 'Life' class that produces the next generation and redraws itself from the center outward, inserting delays to produce a kaleidoscopic effect.
I've got it so that the patterns draw - I took the LunarLander sample as a starting point, and an drawing on a SurfaceView. But my problem is with timing the 'animations'. I'm not doing traditional animation, where I build a whole frame and then draw it, but the surface seems to want to draw itself completely on each iteration of my loop, so my inserted sleep's don't insert delay in the right places.
So my questions:
1. Is there a more direct way to write to the screen than via a SurfaceView? If I did that, would the various steps of my 'animation' occur as I drew them, producing the desired effect. 2. If such a drawing method exists, would I be wasting my time learning how to use it? 3. What's the 'standard' way to do this kind of animation?
View 3 Replies
View Related
Oct 8, 2010
Is there any api for drawing financial chart in android.
View 2 Replies
View Related
Oct 29, 2010
Trying to draw a circle at a longitude/latitude position. The circle below doesn't show up, does anybody know why?
View 5 Replies
View Related
Mar 16, 2010
I have to recommend just getting a book on the subject.I learned most everything off of examples and documents on the web.After several months, I finally picked up the blue book and everything I had scoured to find is clearly demonstrated in it.Look for the red book and the blue "superbible."They cover everything you need.There are also books specific to ES.Make sure to get a good 1.1 one and not a 2.0-only one.
View 7 Replies
View Related
Jun 17, 2009
From the JavaDoc, it said it returns 'a bitmap representing this view or null if cache is disabled'. My question is what if the View is longer than the phone screen (you need to scroll vertically), what does the bitmap return? * only the visible portion of the view * everything the view has (both visible + invisible part)
View 4 Replies
View Related
Aug 10, 2010
Using OpenGL ES, how do I draw an image from the resources file onto the screen? The image is in png format, if that matters.
View 3 Replies
View Related
Nov 29, 2009
I'm trying to create on of these images, but Eclipse won't accept it once I've used the draw9patch tool. I've found other people having the same problem, and saw this comment: I discovered later that the problem I was having was caused by the image not being exactly true to the nine-patch spec as defined in the documentation. Once I fixed the image to have a clean (i.e., no gradients etc) one pixel border it was fine. "'m not much good when it comes to image design. What does this mean, how do I create my original png file to meet the specification for Nine Patch?
View 2 Replies
View Related
Aug 14, 2010
I am creating a custom view which has an image. The image can be of any type. What i want to achieve is that i want to draw an EditText control on top of the image so that the user can add some values to it. I am not sure how to achieve this. The onDraw control will not allow me to draw any view right? I am new to android so any help would be appreaciated.
View 3 Replies
View Related
Apr 5, 2010
I'm trying to build a custom clock view in Android. See image http://twitpic.com/1devk7.So far to draw the time and hour markers I have been using the Canvas.rotate method to get the desired effect. However, notice that it is difficult to interpret the numbers in the lower half of the clock (e.g. 6 or 9?) because of the angle in which they are drawn.When using drawText, is it possible to draw the text at 45/90/180 degrees so that all text appears upright when my onDraw method has finished?
View 1 Replies
View Related
Jan 7, 2010
I wrote a reading software. I implemented the page turning effect when user tap the screen to turn to next/pre page. The display is ok on G1 (320X200 size) but it can not works well on Droid(480*854 size), the font looks a litter fuzzy, not clear as G1. I explain my codes for page turning:
1) create a canvas A
2) create bitmap.
3) set bitmap on canvas A
4) draw the new page content on canvas A
5) the current showing page has been saved in bitmap before since we do from step 1) to setp 4),
6) In order to implement the turning effect of scrolling from left to right, I draw the old bitmap part and draw the new bitmap part until the whole new bitmap has been drawn. all of bitmaps are drawing by canvas.drawBitmap() in onDraw() function.
7) when step 6) is done, it means the new page has been shown on screen, and the bitmap has been saved to use in next page turning.
The above is the whole actions for my page turning. On G1, no problem. But on Droid phone, the font is not clear, I tried if I directly draw text by canvas in OnDraw() not through bitmap, It is ok, but it can not implement the page turning effect that I need. I don't know why, could you please help me to take a look and tell me where is wrong or miss some steps?
View 2 Replies
View Related
Jul 28, 2009
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:........
View 4 Replies
View Related
Oct 8, 2010
How to draw chart like the following image in android.what is the tool can we use?
View 1 Replies
View Related
Aug 27, 2009
I'm trying to scale/rotate an image using setImageMatrix, and it seems to have no effect. I've done a lot of Googling and found some people mentioning similar problems, but found no solution.
View 2 Replies
View Related
Nov 15, 2010
I've got a game, a custom View class draws my gameboard. I'm thinking of drawing some elements on a separate layer above the gameboard. I could do this in the View's canvas code, but since they won't change frequently, was thinking of introducing a frame layout to display this top layer.I'm not sure which route to take, the only reason I wouldn't do the FrameLayout is because I'm not sure if it has an impact on battery life. Everytime onDraw() is called, the system probably has to do an alpha composition of the two layers. Is that more battery consuming than drawing the elements from that layer myself in my canvas on every frame? Hard to answer since I'm not sure how complex the drawing will be yet, any general opinions?
View 1 Replies
View Related
