Question

单击imageview后，我收到IllegalStateException和NullPointerException（App崩溃）。它应该将imageview的图像传递给另一个imageview。我也在为标签活动使用片段。

onCreate（）和变量

private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
PhotoViewAttacher xAttach;
ImageView tessst;

    @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setContentView(R.layout.activity_whole_details);

    tessst = (ImageView) findViewById(R.id.fillZoom);
    what = (ImageView) findViewById(R.id.img1);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

    mViewPager = (ViewPager) findViewById(R.id.container);
    mViewPager.setAdapter(mSectionsPagerAdapter);

    TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
    tabLayout.setupWithViewPager(mViewPager);

}

Imageview点击课程

    public void clickZoom(View v){
    if(v.getId() == R.id.img1){
        Drawable bb = getResources().getDrawable(R.drawable.maincolor_btn);
        tessst.setImageDrawable(bb);
        xAttach = new PhotoViewAttacher(tessst);
    }
}

logcat

09-06 13:12:45.436 31388-31388/com.example.testapp.coloranalysis E/AndroidRuntime: FATAL EXCEPTION: main
               Process: com.example.testapp.coloranalysis, PID: 31388
               java.lang.IllegalStateException: Could not execute method for android:onClick
                   at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:293)
                   at android.view.View.performClick(View.java:4463)
                   at android.view.View$PerformClick.run(View.java:18770)
                   at android.os.Handler.handleCallback(Handler.java:808)
                   at android.os.Handler.dispatchMessage(Handler.java:103)
                   at android.os.Looper.loop(Looper.java:193)
                   at android.app.ActivityThread.main(ActivityThread.java:5323)
                   at java.lang.reflect.Method.invokeNative(Native Method)
                   at java.lang.reflect.Method.invoke(Method.java:515)
                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:824)
                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:640)
                   at dalvik.system.NativeStart.main(Native Method)
                Caused by: java.lang.reflect.InvocationTargetException
                   at java.lang.reflect.Method.invokeNative(Native Method)
                   at java.lang.reflect.Method.invoke(Method.java:515)
                   at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)
                   at android.view.View.performClick(View.java:4463) 
                   at android.view.View$PerformClick.run(View.java:18770) 
                   at android.os.Handler.handleCallback(Handler.java:808) 
                   at android.os.Handler.dispatchMessage(Handler.java:103) 
                   at android.os.Looper.loop(Looper.java:193) 
                   at android.app.ActivityThread.main(ActivityThread.java:5323) 
                   at java.lang.reflect.Method.invokeNative(Native Method) 
                   at java.lang.reflect.Method.invoke(Method.java:515) 
                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:824) 
                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:640) 
                   at dalvik.system.NativeStart.main(Native Method) 
                Caused by: java.lang.NullPointerException
                   at com.example.testapp.coloranalysis.WholeDetails.clickZoom(WholeDetails.java:59)
                   at java.lang.reflect.Method.invokeNative(Native Method) 
                   at java.lang.reflect.Method.invoke(Method.java:515) 
                   at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288) 
                   at android.view.View.performClick(View.java:4463) 
                   at android.view.View$PerformClick.run(View.java:18770) 
                   at android.os.Handler.handleCallback(Handler.java:808) 
                   at android.os.Handler.dispatchMessage(Handler.java:103) 
                   at android.os.Looper.loop(Looper.java:193) 
                   at android.app.ActivityThread.main(ActivityThread.java:5323) 
                   at java.lang.reflect.Method.invokeNative(Native Method) 
                   at java.lang.reflect.Method.invoke(Method.java:515) 
                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:824) 
                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:640) 
                   at dalvik.system.NativeStart.main(Native Method)

Answer 1

也许tessst为空。

因此R.id.fillZoom可能不在R.layout.activity_whole_details

您可以将tessst = (ImageView) findViewById(R.id.fillZoom);移动到片段中的onCreateView，当然与tessst相关联的代码也必须移动。

Answer 2

我假设您在XML中添加了onClick侦听器，其属性为android：onClick =“clickZoom”。现在要做到这一点，clickZoom函数必须是Activity类的一部分，听起来它不是。
您需要做的是删除XML属性，并在代码中设置onClick侦听器，方法是让您的类实现View.OnClickListener接口，并在视图上调用setOnClickListener。

Android：单击按钮后无法设置图像（NullpointerException / IllegalStateException）

2 个答案: