Panfery Panfery - 3 months ago 37
Java Question

Fatal error: main. editText equals for login in android studio

I'm just learning some basics of Java and have little problem with my app

This is part of my MainActivity

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);

FloatingActionButton button = (FloatingActionButton) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
EditText edit = (EditText) findViewById(R.id.editText);
if (edit.getText().toString().equals("admin")) {
Intent gz = new Intent(getApplicationContext(), gz.class);
startActivity(gz);
}

}
});
}


I would like that app changed activity from mainActivity to gz activity after click button and check EditText edit.

At this stage app just crash.


--------- beginning of crash
08-16 12:50:38.284 9345-9345/com.example.fiery.app1 E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.fiery.app1, PID: 9345
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.fiery.app1/com.example.fiery.app1.MainActivity}: java.lang.ClassCastException: android.support.v7.widget.AppCompatButton cannot be cast to android.support.design.widget.FloatingActionButton
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2434)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2494)
at android.app.ActivityThread.access$900(ActivityThread.java:157)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1356)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5551)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:730)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:620)
Caused by: java.lang.ClassCastException: android.support.v7.widget.AppCompatButton cannot be cast to android.support.design.widget.FloatingActionButton
at com.example.fiery.app1.MainActivity.onCreate(MainActivity.java:25)
at android.app.Activity.performCreate(Activity.java:6272)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1108)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2387)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2494) 
at android.app.ActivityThread.access$900(ActivityThread.java:157) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1356) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:148) 
at android.app.ActivityThread.main(ActivityThread.java:5551) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:730) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:620) 

Answer

you are intialize your button in wrong way,You can try to cast yout widget button to FloatingActionButtonyou and it's not possible please just change Like this

Button button = (Button) findViewById(R.id.button);
    button.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v) {
            EditText edit = (EditText) findViewById(R.id.editText);
            if (edit.getText().toString().equals("admin")) {
                Intent gz = new Intent(getApplicationContext(), gz.class);
                startActivity(gz);
            }

        }
    });