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androidmenuimageswitcher

Android Image not switching


I'm working on a piece of code that could switch image using Menu inflater, i've worked on code but it gives me force close error as soon as i click the button. here is my code:

@Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // TODO Auto-generated method stub
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.menu, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // TODO Auto-generated method stub
        switch (item.getItemId()) {
        case R.id.cameraa:
            Toast.makeText(this, "Start Camera!", Toast.LENGTH_LONG).show();
            break;

        case R.id.gallery:
         Toast.makeText(this, "this is gallery!", Toast.LENGTH_LONG).show();
        break;


    public boolean onOptionsItemSelected(MenuItem item) {
        // TODO Auto-generated method stub
        switch (item.getItemId()) {


    case R.id.ghost_gallery:
            switcher.showNext();
break
            }
            return true;
        }

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
 <ViewSwitcher
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1" >

        <FrameLayout
            android:id="@+id/frame"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent" >

        <ImageView
            android:id="@+id/imageView"
            android:layout_width="fill_parent"
            android:layout_height="match_parent"
            android:scaleType="matrix"
            android:src="@drawable/banana" />
        </FrameLayout>

        <FrameLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent" >

        <ImageView
            android:id="@+id/imageView"
            android:layout_width="fill_parent"
            android:layout_height="match_parent"
            android:scaleType="matrix"
            android:src="@drawable/apple" />
        </FrameLayout>
    </ViewSwitcher>

here is my log

05-21 03:19:35.733: E/AndroidRuntime(758): FATAL EXCEPTION: main
05-21 03:19:35.733: E/AndroidRuntime(758): java.lang.NullPointerException
05-21 03:19:35.733: E/AndroidRuntime(758):  at org.example.touch.Touch.nextView(Touch.java:188)
05-21 03:19:35.733: E/AndroidRuntime(758):  at org.example.touch.Touch.onOptionsItemSelected(Touch.java:180)
05-21 03:19:35.733: E/AndroidRuntime(758):  at android.app.Activity.onMenuItemSelected(Activity.java:2195)
05-21 03:19:35.733: E/AndroidRuntime(758):  at com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected(PhoneWindow.java:730)
05-21 03:19:35.733: E/AndroidRuntime(758):  at com.android.internal.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:143)
05-21 03:19:35.733: E/AndroidRuntime(758):  at com.android.internal.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:855)
05-21 03:19:35.733: E/AndroidRuntime(758):  at com.android.internal.view.menu.IconMenuView.invokeItem(IconMenuView.java:532)
05-21 03:19:35.733: E/AndroidRuntime(758):  at com.android.internal.view.menu.IconMenuItemView.performClick(IconMenuItemView.java:122)
05-21 03:19:35.733: E/AndroidRuntime(758):  at android.view.View$PerformClick.run(View.java:8816)
05-21 03:19:35.733: E/AndroidRuntime(758):  at android.os.Handler.handleCallback(Handler.java:587)
05-21 03:19:35.733: E/AndroidRuntime(758):  at android.os.Handler.dispatchMessage(Handler.java:92)
05-21 03:19:35.733: E/AndroidRuntime(758):  at android.os.Looper.loop(Looper.java:123)
05-21 03:19:35.733: E/AndroidRuntime(758):  at android.app.ActivityThread.main(ActivityThread.java:4627)
05-21 03:19:35.733: E/AndroidRuntime(758):  at java.lang.reflect.Method.invokeNative(Native Method)
05-21 03:19:35.733: E/AndroidRuntime(758):  at java.lang.reflect.Method.invoke(Method.java:521)
05-21 03:19:35.733: E/AndroidRuntime(758):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-21 03:19:35.733: E/AndroidRuntime(758):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-21 03:19:35.733: E/AndroidRuntime(758):  at dalvik.system.NativeStart.main(Native Method)

Kindly help me regarding this matter.... Best Regards,


Solution

  • i used

    private void showImage() {
    
            Toast.makeText(Touch.this, " User don't  ", Toast.LENGTH_SHORT);
            ImageView imgView = (ImageView) findViewById(R.id.imageView);
            imgView.setImageResource(mImageIds[image_index]);
    
        }
    
        @Override
        public void onClick(View v) {
    
            switch (v.getId()) {
    
            case (R.id.previous_btn):
    
                image_index--;
    
                if (image_index == -1) {
                    image_index = MAX_IMAGE_COUNT - 1;
                }
    
                showImage();
                break;
    }}
    

    which works pretty well for me...