Ich versuche einen Android-Code zu erstellen, der für jede Schaltfläche eine andere Arbeit bereitstellt.TEXTVIEW Substantiation location
so, wenn der Benutzer Druck auf Button1 ein Textview Feld bietet
„Sie auf Button1 gedrückt“meine Frage bezieht sich auf die richtige Stelle, die ich nur einmal Textview instanziiert kann als der einzige Arbeitsplatz innerhalb der Funktion Button1 ist .
Java-Code für eine einzige Taste:
public void Button1(View view) {
final TextView textView=(TextView)findViewById(R.id.textView2);
textView.setText("You clicked the button 1");
}
gesamten Java-Code
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
public void Button1(View view) {
final TextView textView=(TextView)findViewById(R.id.textView2);
textView.setText("You clicked the button 1");
}
public void Button2(View view) {
final TextView textView=(TextView)findViewById(R.id.textView2);
textView.setText("You clicked the button 2");
}
public void Button3(View view) {
final TextView textView=(TextView)findViewById(R.id.textView2);
textView.setText("You clicked the button 3");
}
public void Button4(View view) {
final TextView textView=(TextView)findViewById(R.id.textView2);
textView.setText("You clicked the button 4");
}
public void Button5(View view) {
final TextView textView=(TextView)findViewById(R.id.textView2);
textView.setText("You clicked the button 5");
}
public void Button6(View view) {
final TextView textView=(TextView)findViewById(R.id.textView2);
textView.setText("You clicked the button 6");
}
}
Gesamt XML-Code
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/RelativeLayoutID"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="com.example.sherifsaleh.xmllayout.MainActivity"
tools:showIn="@layout/activity_main"
>
<Button
android:id="@+id/button3"
android:onClick="Button3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="3"
android:layout_above="@+id/button6"
android:layout_alignLeft="@+id/button6"
android:layout_alignStart="@+id/button6" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="Button6"
android:text="6"
android:id="@+id/button6"
android:layout_below="@+id/button2"
android:layout_alignLeft="@+id/button9"
android:layout_alignStart="@+id/button9" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="9"
android:id="@+id/button9"
android:onClick="Button9"
android:layout_alignTop="@+id/button8"
android:layout_toRightOf="@+id/button8"
android:layout_toEndOf="@+id/button8" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="8"
android:id="@+id/button8"
android:layout_below="@+id/button5"
android:layout_toRightOf="@+id/button4"
android:layout_toEndOf="@+id/button4"
android:onClick="Button8"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="2"
android:onClick="Button2"
android:id="@+id/button2"
android:layout_above="@+id/button5"
android:layout_toRightOf="@+id/button1"
android:layout_toEndOf="@+id/button1" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="Button5"
android:text="5"
android:id="@+id/button5"
android:layout_below="@+id/button1"
android:layout_toRightOf="@+id/button1"
android:layout_toEndOf="@+id/button1" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="1"
android:onClick="Button1"
android:layout_above="@+id/button4"
android:layout_alignLeft="@+id/button4"
android:layout_alignStart="@+id/button4" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="4"
android:id="@+id/button4"
android:layout_above="@+id/button7"
android:layout_alignLeft="@+id/button7"
android:layout_alignStart="@+id/button7" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="7"
android:id="@+id/button7"
android:layout_alignParentBottom="true"
android:layout_alignLeft="@+id/textView2"
android:layout_alignStart="@+id/textView2"
android:layout_marginBottom="90dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textIsSelectable="true"
android:text="New Text"
android:id="@+id/textView2"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="80dp"
android:textSize="50dp"/>
</RelativeLayout>
deklarieren Sie es als Klassenmitglied und führen Sie die Initialisierung in 'onCreate.' Es wird einmal während des Lebenszyklus der Aktivität aufgerufen. – Raghunandan
@sherif - vergessen Sie nicht, eine Antwort zu akzeptieren. Somias Antwort ist die vollständigste. – JohnnyLambada