Anything that touches/modifies/updates the UI MUST run on the UI thread... On May 1, 2012 12:44 PM, "Jonathan S" <[email protected]> wrote:
> Any class is under View NEEDS to be in the Main Thread. > > On Tuesday, May 1, 2012 2:09:15 PM UTC-4, Ab wrote: >> >> This TestActivity mimics some behavior in my app, which casues an ANR on >> the Samsung Note ( running Android version 2.3.6). It did not produce an >> ANR on a few other devices I tried, including 2 different Samsung devices >> both with 2.3.6. >> >> Based on the traces.txt file, the GUI thread appears to get stuck while >> painting an ImageButton. No idea why this happens, but the traces.txt is >> pastebin-ed below. >> >> The Activity creates a layout with a lot of ImageButtons, each of which >> will cause the entire layout to invalidate when pressed. It then starts a >> new thread which renders a Bitmap into a canvas. The Bitmap is painted >> into the canvas one line at a time, by using Canvas.drawBitmap(int[]....); >> the ANR occurs regardless of the pixel values of the Bitmap, so the test >> app just uses an instantiated int[] (in which all values are 0). If I >> randomly press the buttons on the screen, the application will ANR after >> 10-30seconds. >> >> I don't think the ANR is dependent on the width and height values of the >> Bitmap being rendered, or the dimensions of the Bitmap that is used as the >> parameter in the Canvas' constructor. However, it is dependent on the >> canvas.scale(.36f, .36f) that occurs prior to the bitmap rendering. I'm >> not sure if values other than ".36" cause the ANR, but the ANR does not >> occur if no scaling happens prior to the drawBitmap call. Also, the ANR >> does not occur unless the Canvas object is created with a Bitmap as its >> parameter. >> >> So, my guess is that this is somehow related to the Samsung Note's native >> implementation of Canvas.drawBitmap. Any ideas what would cause the GUI >> thread to be blocked and how it can be prevented? >> >> http://pastebin.com/hummn87H >> >> public class TempActivity extends Activity implements >> android.view.View.**OnClickListener >> { >> LinearLayout contentView; >> public void onCreate(Bundle savedInstanceState) >> { >> super.onCreate(**savedInstanceState); >> >> Log.e("", ""+1); >> >> contentView = new LinearLayout(this); >> contentView.setOrientation(**LinearLayout.VERTICAL); >> >> //add a few rows of image buttons >> contentView.addView(initRow())**; >> contentView.addView(initRow())**; >> contentView.addView(initRow())**; >> contentView.addView(initRow())**; >> contentView.addView(initRow())**; >> contentView.addView(initRow())**; >> >> setContentView(contentView); >> >> RenderThread task1 = new RenderThread(); >> task1.start(); >> } >> >> public class RenderThread extends Thread >> { >> public void run() >> { >> Paint paint = new Paint(); >> Bitmap bitmap = Bitmap.createBitmap(500, 500, >> Config.ARGB_8888); >> >> int width = 800; >> int height = 1000; >> >> int[] pixels = new int[width]; >> >> while (1!= 0) >> { >> Canvas canvas = new Canvas(bitmap); >> canvas.scale(.36f, .36f); >> for(int i = 0; i < height; i++) >> { >> canvas.drawBitmap(pixels, 0, width, 0, i, width, 1, false, paint); >> } >> } >> } >> } >> >> private View initRow() >> { >> LinearLayout row = new LinearLayout(this); >> row.setOrientation(**LinearLayout.HORIZONTAL); >> ImageButton button = new ImageButton(this); >> button.setImageResource(R.**drawable.icon); >> button.setOnClickListener(**this); >> row.addView(button); >> button = new ImageButton(this); >> button.setImageResource(R.**drawable.icon); >> button.setOnClickListener(**this); >> row.addView(button); >> button = new ImageButton(this); >> button.setImageResource(R.**drawable.icon); >> button.setOnClickListener(**this); >> row.addView(button); >> button = new ImageButton(this); >> button.setImageResource(R.**drawable.icon); >> button.setOnClickListener(**this); >> row.addView(button); >> button = new ImageButton(this); >> button.setImageResource(R.**drawable.icon); >> button.setOnClickListener(**this); >> row.addView(button); >> button = new ImageButton(this); >> button.setImageResource(R.**drawable.icon); >> button.setOnClickListener(**this); >> row.addView(button); >> >> return row; >> } >> >> @Override >> public void onClick(View v) >> { >> contentView.postInvalidate(); >> } >> } >> >> -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
