Android Studio：应用合并发布资源FAILD

Question

`public class MainActivity extends Activity {     ImageButton button1;     ImageButton button2;     ImageButton button3;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    addListenerOnButton();
}
public void addListenerOnButton(){
    button1 = (ImageButton)findViewById(R.id.Button1);
    button1.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent();
            intent.setClass(MainActivity.this, SecondActivity.class);
            startActivity(intent);
        }
    });
    button2 = (ImageButton)findViewById(R.id.Button2);
    button2.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent();
            intent.setClass(MainActivity.this, ThirdActivity.class);
            startActivity(intent);
        }
    });
    button3 = (ImageButton)findViewById(R.id.Button3);
    button3.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent();
            intent.setClass(MainActivity.this, ForthActivity.class);
            startActivity(intent);
        }
    });

}

} `我坚持使用Android Studio构建apk。消息Gradle Build始终显示“：app：mergeReleaseResource FAILD”。我想知道.png文件是否有问题。The picture shows the details in Messages Gradle Build