Delete Canvas - Fill Canvas Android example
Fill the entire canvas with the specified color.
@Override
public void onDraw(Canvas canvas) {
canvas.drawColor(Color.GREEN);
}
396LW NO topic_id
AD
Další témata ....(Topics)
Problemi is in e.getMessage() what can return null and Log.e (String tag, String msg) will throws an new exception !!!!
Problem and solution:
LogCat:
Or you can using this code:
Problem and solution:
try {
int [] i = {1};
int z = i[5];
} catch (ArrayIndexOutOfBoundsException e) {
String s = e.toString(); // s == java.lang.ArrayIndexOutOfBoundsException
// try to testing String s for null value
if(s != null)
Log.e("bla", s);
else
Log.e("bla", "My error text 1");
String s2 = e.getMessage(); // s2 == null !!!!!!!
// you need to testing String s2 for null value , or you get FATAL EXCEPTION: main
// and application will be crashed
String s2 = e.getMessage(); // s2 == null !!!!!!!
if(s2 != null)
Log.e("bla2", e.getMessage());
else
Log.e("bla2", "My error text 2");
// this is OK
e.printStackTrace();
}
LogCat:
E/bla(855): java.lang.ArrayIndexOutOfBoundsException
E/bla2(855): My error text 2
W/System.err(855): java.lang.ArrayIndexOutOfBoundsException
W/System.err(855): at cz.okhelp.motion._MotionActivity.onTouchEvent(_MotionActivity.java:54)
W/System.err(855): at android.app.Activity.dispatchTouchEvent(Activity.java:2099)
W/System.err(855): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1675)
W/System.err(855): at android.view.ViewRoot.deliverPointerEvent(ViewRoot.java:2194)
W/System.err(855): at android.view.ViewRoot.handleMessage(ViewRoot.java:1878)
W/System.err(855): at android.os.Handler.dispatchMessage(Handler.java:99)
W/System.err(855): at android.os.Looper.loop(Looper.java:123)
W/System.err(855): at android.app.ActivityThread.main(ActivityThread.java:3683)
W/System.err(855): at java.lang.reflect.Method.invokeNative(Native Method)
W/System.err(855): at java.lang.reflect.Method.invoke(Method.java:507)
W/System.err(855): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
W/System.err(855): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
W/System.err(855): at dalvik.system.NativeStart.main(Native Method)
Or you can using this code:
try {
int [] i = {1};
int z = i[5];
} catch (Exception e) {
StringBuilder sb = new StringBuilder().append(e.getClass().getSimpleName());
if (e.getMessage() != null) {
sb.append("
");
sb.append(e.getMessage());
}
Log.e("err", sb.toString()); // E/err(336): ArrayIndexOutOfBoundsException
// this code write out all message
Log.e("myError", "methodName", e);
}
// E/myError(371): methodName
// E/myError(371): java.lang.ArrayIndexOutOfBoundsException
// E/myError(371): at cz.okhelp.motion._MotionActivity.onTouchEvent(_MotionActivity.java:54)
// E/myError(371): at android.app.Activity.dispatchTouchEvent(Activity.java:2099)
// E/myError(371): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1675)
// E/myError(371): at android.view.ViewRoot.deliverPointerEvent(ViewRoot.java:2194)
// E/myError(371): at android.view.ViewRoot.handleMessage(ViewRoot.java:1878)
// E/myError(371): at android.os.Handler.dispatchMessage(Handler.java:99)
// E/myError(371): at android.os.Looper.loop(Looper.java:123)
// E/myError(371): at android.app.ActivityThread.main(ActivityThread.java:3683)
// E/myError(371): at java.lang.reflect.Method.invokeNative(Native Method)
// E/myError(371): at java.lang.reflect.Method.invoke(Method.java:507)
// E/myError(371): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
// E/myError(371): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
// E/myError(371): at dalvik.system.NativeStart.main(Native Method)
If you using Context as parameter of function try this solution:
public class MyActivity extends Activity {
// bla bla bla .......
//error
myFc( getapplicationcontext());
// OK
myFc(MyActivity.this);
public class Panel extends SurfaceView implements SurfaceHolder.Callback {
//............... code
//............... some code
/**
* Process the MotionEvent.
*/
@Override
public boolean onTouchEvent(MotionEvent event) {
synchronized (getHolder()) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
performClick();
} else if (event.getAction() == MotionEvent.ACTION_MOVE) {
if(_currentGraphic==null)return true;
} else if (event.getAction() == MotionEvent.ACTION_UP) {
}
return true;
}
}
/////////////////////////////
@Override
public boolean performClick() {
// Calls the super implementation, which generates an AccessibilityEvent
// and calls the onClick() listener on the view, if any
super.performClick();
// Handle the action for the custom click here
return true;
}
}
Code with error:
If you get error try this code:
java.lang.ClassCastException: android.view.ViewGroup$LayoutParams
at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:659)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:311)
at android.view.View.measure(View.java:8313)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:386)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:309)
at android.view.View.measure(View.java:8313)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:250)
at android.view.View.measure(View.java:8313)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:531)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:309)
at android.view.View.measure(View.java:8313)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:250)
at android.view.View.measure(View.java:8313)
ImageView imgV = (ImageView)findViewById(R.id.myView);
imgV.setLayoutParams(new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
0));
If you get error try this code:
ViewGroup.LayoutParams layoutParams = imgV
.getLayoutParams();
layoutParams.height = 0;
imgV.setLayoutParams(layoutParams);
java.lang.ClassCastException: android.view.ViewGroup$LayoutParams
at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:659)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:311)
at android.view.View.measure(View.java:8313)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:386)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:309)
at android.view.View.measure(View.java:8313)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:250)
at android.view.View.measure(View.java:8313)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:531)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:309)
at android.view.View.measure(View.java:8313)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:250)
at android.view.View.measure(View.java:8313)
Spinner, ArrayAdapter, setOnItemSelectedListener, onItemSelected, setDropDownViewResource
MainClass.java
strings.xml
MainClass.java
public class Vypocet extends Activity {
Spinner hSpinnerMetry;
// .......
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
hSpinnerMetry = (Spinner) findViewById(R.id.idSpinnerMetry);
ArrayAdapter<CharSequence> adapterMetry = ArrayAdapter.createFromResource(
this, R.array.metry_array, android.R.layout.simple_spinner_item);
adapterMetry.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
hSpinnerMetry.setAdapter(adapterMetry);
hSpinnerMetry.setOnItemSelectedListener(
new OnItemSelectedListener() {
public void onItemSelected(
AdapterView<?> parent, View view, int position, long id) {
int nPos = position;
}
public void onNothingSelected(AdapterView<?> parent) {
}
});
}
}
strings.xml
<string-array name="metry_array">
<item>m</item>
<item>dm</item>
<item>cm</item>
<item>mm</item>
</string-array>
Editace: 2013-12-09 13:04:00
Počet článků v kategorii: 396
Url:delete-canvas-fill-canvas-android-example