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public class MainActivity extends AppCompatActivity implements View.OnClickListener{
 
    TextView tx;
    Button bt;
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        tx = (TextView) this.findViewById(R.id.textView1);
        bt = (Button) this.findViewById(R.id.button1);
        tx.setOnClickListener(this);
        bt.setOnClickListener(this);
 
    }
 
    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.textView1:
                tx.setText("點擊了TextView");
                break;
            case R.id.button1:
                tx.setText("點擊了Button");
                break;
        }
 
    }
}
 
 

Main.java:1: error: class MainActivity is public, should be declared in a file named MainActivity.java
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
       ^
Main.java:1: error: cannot find symbol
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
                                  ^
  symbol: class AppCompatActivity
Main.java:1: error: package View does not exist
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
                                                                   ^
Main.java:3: error: cannot find symbol
    TextView tx;
    ^
  symbol:   class TextView
  location: class MainActivity
Main.java:4: error: cannot find symbol
    Button bt;
    ^
  symbol:   class Button
  location: class MainActivity
Main.java:7: error: cannot find symbol
    protected void onCreate(Bundle savedInstanceState) {
                            ^
  symbol:   class Bundle
  location: class MainActivity
Main.java:19: error: cannot find symbol
    public void onClick(View v) {
                        ^
  symbol:   class View
  location: class MainActivity
Main.java:6: error: method does not override or implement a method from a supertype
    @Override
    ^
Main.java:8: error: cannot find symbol
        super.onCreate(savedInstanceState);
        ^
  symbol:   variable super
  location: class MainActivity
Main.java:9: error: package R does not exist
        setContentView(R.layout.activity_main);
                        ^
Main.java:11: error: cannot find symbol
        tx = (TextView) this.findViewById(R.id.textView1);
              ^
  symbol:   class TextView
  location: class MainActivity
Main.java:11: error: package R does not exist
        tx = (TextView) this.findViewById(R.id.textView1);
                                           ^
Main.java:12: error: cannot find symbol
        bt = (Button) this.findViewById(R.id.button1);
              ^
  symbol:   class Button
  location: class MainActivity
Main.java:12: error: package R does not exist
        bt = (Button) this.findViewById(R.id.button1);
                                         ^
Main.java:18: error: method does not override or implement a method from a supertype
    @Override
    ^
Main.java:21: error: package R does not exist
            case R.id.textView1:
                  ^
Main.java:24: error: package R does not exist
            case R.id.button1:
                  ^
17 errors

Standard output is empty