如何在android中的onClick方法中创建一个事件

Question

我的要求是单击图像我应该由alertbuilder发出警报.它发生得非常好.在alertbuilder中我指的是一个布局.然后我引用了小部件的ID.然后在这个onclick方法的范围内,我为这些小部件做了动作.

holder.source.setOnClickListener(new View.OnClickListener() {

                @Override
                public void onClick(View v) {
                Toast.makeText(getApplicationContext(), "Source",Toast.LENGTH_LONG).show();
                dialog = new Dialog(RecordingActivity2.this);
                dialog.setTitle("Source File");
                dialog.setContentView(R.layout.activity_read);
                ImageButton im = (ImageButton)findViewById(R.id.close);
                im.setOnClickListener(new View.OnClickListener() {

                    @Override
                    public void onClick(View v) {
                    **If i am making actions here application is closing unexpectedly.**

                    }
                });
                dialog.show();
                }
            });

这是我的logcat输出

07-04 17:25:29.923: E/AndroidRuntime(1928): FATAL EXCEPTION: main
07-04 17:25:29.923: E/AndroidRuntime(1928): java.lang.NullPointerException
07-04 17:25:29.923: E/AndroidRuntime(1928):     at com.pdev.activities.RecordingActivity2$VehicleAdapter$1.onClick(RecordingActivity2.java:209)
07-04 17:25:29.923: E/AndroidRuntime(1928):     at android.view.View.performClick(View.java:3480)
07-04 17:25:29.923: E/AndroidRuntime(1928):     at android.view.View$PerformClick.run(View.java:13983)
07-04 17:25:29.923: E/AndroidRuntime(1928):     at android.os.Handler.handleCallback(Handler.java:605)
07-04 17:25:29.923: E/AndroidRuntime(1928):     at android.os.Handler.dispatchMessage(Handler.java:92)
07-04 17:25:29.923: E/AndroidRuntime(1928):     at android.os.Looper.loop(Looper.java:137)
07-04 17:25:29.923: E/AndroidRuntime(1928):     at android.app.ActivityThread.main(ActivityThread.java:4340)

Answer 1

更换

ImageButton im = (ImageButton)findViewById(R.id.close);

至

ImageButton im = (ImageButton)dialog.findViewById(R.id.close);