R cannot be resolved to a variable
Check your xml files in Eclipse Graphical Editor and fix problems.
Check project setup, right click on project, select properties, Java build path and
select correct Android version etc.
Right click on project, Android Tools, Fix Project Properties
Menu Eclipse select Project ->Clean.
Check project setup, right click on project, select properties, Java build path and
select correct Android version etc.
Right click on project, Android Tools, Fix Project Properties
Menu Eclipse select Project ->Clean.
397LW NO topic_id
Další témata ....(Topics)
Put extends PreferenceFragment API level 11 instead PreferenceActivity
public class SettingsActivity extends PreferenceFragment {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.preferences);
}
}
// or insert suppresswarning
public class SettingsActivity extends PreferenceActivity {
@SuppressWarnings("deprecation")
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.preferences);
}
}
Canvas, drawLine(), setStrokeWidth(), Paint, setAntiAlias(boolean), onDraw()
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(new SampleView(this));
}
private static class SampleView extends View {
// CONSTRUCTOR
public SampleView(Context context) {
super(context);
setFocusable(true);
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(Color.YELLOW);
Paint p = new Paint();
// smooths
p.setAntiAlias(true);
p.setColor(Color.RED);
p.setStrokeWidth(4.5f);
// opacity
p.setAlpha(0x80); //
// drawLine (float startX, float startY, float stopX, float stopY,
// Paint paint)
canvas.drawLine(0, 0, 40, 40, p);
canvas.drawLine(40, 0, 0, 40, p);
}
}
}
How get Android SDK location - PATH on PC from Eclipse tutorial.
- Open dialog from menu Window -> AVD and SDK manager
- In dialog select Available packages
- On top of dialog will displayed similar path: SKD Location: C:\PROGRA~1\Android\android-sdk-windows\
If you do click on Rebuid project menu item, this operation maybe consume long time on slovly PC.
Some errors dismis when you do rebuild project, or module.
Try this:
Select module where contains red error code and press Debugg or Run button on Android Studio.
If module code contains errors, Android Studio show error report in gradle console.
If not, apk will installed on device.
This is 10 times faster than Clean - Rebuild all project.
Some errors dismis when you do rebuild project, or module.
Try this:
Select module where contains red error code and press Debugg or Run button on Android Studio.
If module code contains errors, Android Studio show error report in gradle console.
If not, apk will installed on device.
This is 10 times faster than Clean - Rebuild all project.
////www.apache.org/licenses/LICENSE-2.0
private Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
private ColorMatrix mCM = new ColorMatrix();
private Bitmap mBitmap;
private float mSaturation;
private float mAngle;
//..........
mBitmap = BitmapFactory.decodeResource(context.getResources(),
R.drawable.my_image);
//..........
private static void setContrastScaleOnly(ColorMatrix cm, float contrast) {
float scale = contrast + 1.f;
float translate = (-.5f * scale + .5f) * 255.f;
cm.set(new float[] {
scale, 0, 0, 0, 0,
0, scale, 0, 0, 0,
0, 0, scale, 0, 0,
0, 0, 0, 1, 0 });
}
private static void setContrast(ColorMatrix cm, float contrast) {
float scale = contrast + 1.f;
float translate = (-.5f * scale + .5f) * 255.f;
cm.set(new float[] {
scale, 0, 0, 0, translate,
0, scale, 0, 0, translate,
0, 0, scale, 0, translate,
0, 0, 0, 1, 0 });
}
private static void setContrastTranslateOnly(ColorMatrix cm, float contrast) {
float scale = contrast + 1.f;
float translate = (-.5f * scale + .5f) * 255.f;
cm.set(new float[] {
1, 0, 0, 0, translate,
0, 1, 0, 0, translate,
0, 0, 1, 0, translate,
0, 0, 0, 1, 0 });
}
@Override protected void onDraw(Canvas canvas) {
Paint paint = mPaint;
float x = 20;
float y = 20;
canvas.drawColor(Color.WHITE);
paint.setColorFilter(null);
canvas.drawBitmap(mBitmap, x, y, paint);
ColorMatrix cm = new ColorMatrix();
mAngle += 2;
if (mAngle > 180) {
mAngle = 0;
}
//convert our animated angle [-180...180] to a contrast value of [-1..1]
float contrast = mAngle / 180.f;
setContrast(cm, contrast);
paint.setColorFilter(new ColorMatrixColorFilter(cm));
canvas.drawBitmap(mBitmap, x + mBitmap.getWidth() + 10, y, paint);
setContrastScaleOnly(cm, contrast);
paint.setColorFilter(new ColorMatrixColorFilter(cm));
canvas.drawBitmap(mBitmap, x, y + mBitmap.getHeight() + 10, paint);
setContrastTranslateOnly(cm, contrast);
paint.setColorFilter(new ColorMatrixColorFilter(cm));
canvas.drawBitmap(mBitmap, x, y + 2*(mBitmap.getHeight() + 10),
paint);
invalidate();
}
}
Editace: 2014-02-15 20:14:31
Počet článků v kategorii: 397
Url:r-cannot-be-resolved-to-a-variable
