Wie füge ich eine Schaltfläche dynamisch in Android hinzu?

Wie füge ich eine Schaltfläche dynamisch in Android hinzu?

Button myButton = new Button(this);
myButton.setText("Push Me");

LinearLayout ll = (LinearLayout)findViewById(R.id.buttonlayout);
LayoutParams lp = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
ll.addView(myButton, lp);

Schauen Sie sich dieses Beispiel an

Versuche dies:

for (int i = 1; i <= 20; i++) {
    LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
            LinearLayout.LayoutParams.MATCH_PARENT,
            LinearLayout.LayoutParams.WRAP_CONTENT);
    Button btn = new Button(this);
    btn.setId(i);
    final int id_ = btn.getId();
    btn.setText("button " + id_);
    btn.setBackgroundColor(Color.rgb(70, 80, 90));
    linear.addView(btn, params);
    btn1 = ((Button) findViewById(id_));
    btn1.setOnClickListener(new View.OnClickListener() {
        public void onClick(View view) {
            Toast.makeText(view.getContext(),
                    "Button clicked index = " + id_, Toast.LENGTH_SHORT)
                    .show();
        }
    });
}

Versuche dies:

LinearLayout ll = (LinearLayout)findViewById(R.id.layout);

Button btn = new Button(this);
btn.setText("Manual Add");
btn.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
ll.addView(btn);

Versuche dies

private void createLayoutDynamically(int n) {

    for (int i = 0; i < n; i++) {
        Button myButton = new Button(this);
        myButton.setText("Button :"+i);
        myButton.setId(i);
        final int id_ = myButton.getId();

        LinearLayout layout = (LinearLayout) findViewById(R.id.myDynamicLayout);
        layout.addView(myButton);

        myButton.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
                Toast.makeText(DynamicLayout.this,
                        "Button clicked index = " + id_, Toast.LENGTH_SHORT)
                        .show();
            }
        });
    }

for (int k = 1; k < 100; k++) {
    TableRow row = new TableRow(this);

    innerloop:
    for (int l = 1; l < 4; l++) {
        btn = new Button(this);
        TableRow.LayoutParams tr = new TableRow.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
        layout.setWeightSum(12.0f);
        tr.weight = 0;
        btn.setLayoutParams(tr); 
        btn.setTextColor(a);
        btn.setHeight(150);

        btn.setWidth(150);
        btn.setId(idb);
        btn.setText("Button " + idb);
        row.addView(btn);
    }
}

Versuchen Sie diesen Code

 Button btn=new Button(this);
btn.setId(btn);
btn.setBackgroundResource(R.drawable.image);
btn.setMinimumHeight(150);
btn.setMinimumWidth(150);
Relativelayout.addView(btn); 

Versuchen Sie diesen Code. Es wird gut funktionieren ..

public class DynamicViewsActivity extends Activity {

Button button;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    //setContentView(R.layout.activity_dynamic_views);
    ScrollView scrl=new ScrollView(this);
    final LinearLayout ll=new LinearLayout(this);
    ll.setOrientation(LinearLayout.HORIZONTAL);
    LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
            LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
    layoutParams.setMargins(100, 500, 100, 200);
    scrl.addView(ll);
    Button add_btn=new Button(this);
    add_btn.setText("Click Here");

    ll.addView(add_btn, layoutParams);


    final Context context = this;

    add_btn.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub

            Intent intent = new Intent(context, App2Activity.class);
            startActivity(intent);
        }
    });
    this.setContentView(scrl);
}
}

Überprüfen Sie dies.

LinearLayout ll_Main  = new LinearLayout(getActivity());
LinearLayout ll_Row01 = new LinearLayout(getActivity());
LinearLayout ll_Row02 = new LinearLayout(getActivity());

ll_Main.setOrientation(LinearLayout.VERTICAL);
ll_Row01.setOrientation(LinearLayout.HORIZONTAL);
ll_Row02.setOrientation(LinearLayout.HORIZONTAL);

final Button button01    = new Button(getActivity());
final Button button02    = new Button(getActivity());   
final Button button03    = new Button(getActivity());
final Button button04    = new Button(getActivity());

ll_Row01.addView(button01);
ll_Row01.addView(button02);

ll_Row02.addView(button03);
ll_Row02.addView(button04);

ll_Main.addView(ll_Row01);
ll_Main.addView(ll_Row02);

button04.setVisibility(View.INVISIBLE);
button04.setVisibility(View.VISIBLE);

Versuchen Sie folgenden Code.

LinearLayout layout = (LinearLayout) findViewById(R.id.llayout); 
layout.setOrientation(LinearLayout.VERTICAL);

Button btn = new Button(this);
btn.setText("Button1");

layout.add(btn);

btn = new Button(this);
btn.setText(Button2);
layout.add(btn);

Auf diese Weise fügen Sie Schaltflächen gemäß Ihren Anforderungen hinzu.

public void add_btn() {

    lin_btn.setWeightSum(3f);
    for (int j = 0; j < 3; j++) {
        LinearLayout.LayoutParams params1 = new LinearLayout.LayoutParams(
                LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
        params1.setMargins(10, 0, 0, 10);
        params1.weight = 1.0f;

        LinearLayout ll;
        ll = new LinearLayout(this);
        ll.setGravity(Gravity.CENTER_VERTICAL);
        ll.setOrientation(LinearLayout.HORIZONTAL);
        ll.setLayoutParams(params1);

        final Button btn;
        btn = new Button(DynamicActivity.this);

        btn.setText("A"+(j+1));
        btn.setTextSize(15);
        btn.setId(j);
        btn.setPadding(10, 8, 10, 10);

        ll.addView(btn);

        lin_btn.addView(ll);


        btn.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {

                if(v.getId()==0)
                {
                    txt_text.setText("Hii");
                }else if(v.getId()==1)
                {
                    txt_text.setText("hello");
                }else if(v.getId()==2)
                {
                    txt_text.setText("how r u");
                }



            }
        });
    }

}

Eigentlich füge ich der XML-Layoutdatei alles hinzu, was verwendet werden könnte! Dann erhalte ich aus dem Quellcode der spezifischen Aktivität das Objekt anhand seiner ID und "spiele" mit der Sichtbarkeitsmethode.

Hier ist ein Beispiel:

((Spinner)findViewById(R.id.email_spinner)).setVisibility(View.GONE);

Ich habe diesen (oder einen sehr ähnlichen) Code verwendet, um einem LinearLayout mehrere TextViews hinzuzufügen:

// Quick & dirty pre-made list of text labels...
String names[] = {"alpha", "beta", "gamma", "delta", "epsilon"};
int namesLength = 5;

// Create a LayoutParams...
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
    LinearLayout.LayoutParams.WRAP_CONTENT, 
    LinearLayout.LayoutParams.FILL_PARENT);

// Get existing UI containers...
LinearLayout nameButtons = (LinearLayout) view.findViewById(R.id.name_buttons);
TextView label = (TextView) view.findViewById(R.id.master_label);

TextView tv;

for (int i = 0; i < namesLength; i++) {
    // Grab the name for this "button"
    final String name = names[i];

    tv = new TextView(context);
    tv.setText(name);

    // TextViews CAN have OnClickListeners
    tv.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            label.setText("Clicked button for " + name); 
        }
    });

    nameButtons.addView(tv, params);
}

Der Hauptunterschied zwischen diesem und dem Code von dicklaw795 besteht darin, dass die ID nicht für jede Textansicht festgelegt () und erneut abgerufen () wird. Ich fand sie unnötig, obwohl ich sie möglicherweise benötige, um später jede Schaltfläche in einer allgemeinen Handlerroutine zu identifizieren (). zB eine von onClick () für jede TextView aufgerufene).

Button btn = new Button(this);
btn.setText("Submit");
LinearLayout linearLayout = (LinearLayout)findViewById(R.id.buttonlayout);
LayoutParams buttonlayout = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
linearLayout.addView(btn, buttonlayout);

Button myButton = new Button(this);
myButton.setId(123);
myButton.setText("Push Me");


LinearLayout ll = (LinearLayout)findViewById(R.id.buttonlayout);
LayoutParams lp = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
ll.addView(myButton, lp);
 myButton.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
                Toast.makeText(DynamicLayout.this,
                        "Button clicked index = " + id_, Toast.LENGTH_SHORT)
                        .show();
            }
        });

Wenn Sie dynamisch Schaltflächen hinzufügen möchten, versuchen Sie Folgendes:

public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main2);
    for (int i = 1; i <= 5; i++) {
        LinearLayout layout = (LinearLayout) findViewById(R.id.myLinearLayout);
        layout.setOrientation(LinearLayout.VERTICAL);
        Button btn = new Button(this);
        btn.setText("    ");
        layout.addView(btn);
    }

}

Sie können ein Basislayout für Ihre Schaltfläche erstellen und nur das, was spezifisch ist, dynamisch ändern, wie dieses Projekt, das ich erstellt habe, um verschiedene Übungen aus einem Materialdesign-Kurs auszuführen, an dem ich teilnehme:

In diesem Beispiel verwende ich einen vorkonfigurierten AppCompatButton:

layout_base_button.xml

<android.support.v7.widget.AppCompatButton
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/btn_base"
    android:layout_width="200dp"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:layout_marginTop="8dp"
    style="@style/RaisedButton"
    >

</android.support.v7.widget.AppCompatButton>


<style name="RaisedButton" parent="Widget.AppCompat.Button.Colored">
    <item name="android:textSize">11sp</item>
    <item name="android:textStyle">bold</item>
</style>

Und in der habe MainActivityich einige Instanzen erstellt und geändert, was ich brauche, wie den Schaltflächentext und das onClick-Ereignis:

<ScrollView
    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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="udemy.android.materialdesign.MainActivity">

    <LinearLayout
        android:id="@+id/base_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        >

    </LinearLayout>


</ScrollView>



public class MainActivity extends AppCompatActivity {


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        LinearLayout baseLayout = findViewById(R.id.base_layout);

        baseLayout.addView(createButton("TextFields", baseLayout,
                view -> startActivity(createIntent(TextFieldsActivity.class))
        ));

        baseLayout.addView(createButton("Buttons", baseLayout,
                view -> startActivity(createIntent(ButtonsActivity.class))
        ));

        baseLayout.addView(createButton("Toolbar", baseLayout,
                view -> startActivity(createIntent(ToolbarActivity.class))
        ));

    }

    private View createButton(String text, LinearLayout baseLayout, View.OnClickListener onClickEvent) {
        View inflated = LayoutInflater.from(this).inflate(R.layout.layout_base_button, baseLayout, false);
        AppCompatButton btnBase = inflated.findViewById(R.id.btn_base);

        btnBase.setText(text);
        btnBase.setOnClickListener(onClickEvent);
        return btnBase;
    }

    private Intent createIntent(Class<?> cls) {
        return new Intent(this, cls);
    }
}

Entschuldigung für die Verspätung...

In mainactivity.xmlschreiben:

<Button
    android:id="@+id/search"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Search" 
    android:visibility="invisible"/>

In main.javaschreiben:

Button buttonSearch;
buttonSearch = (Button)findViewById(R.id.search);
buttonSearch.setVisibility(View.VISIBLE);