Hoe voeg je dynamisch een knop toe in Android?
Antwoord 1, autoriteit 100%
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);
Bekijk ditvoorbeeld
Antwoord 2, autoriteit 43%
probeer dit:
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();
}
});
}
Antwoord 3, autoriteit 9%
Probeer dit:
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);
Antwoord 4, autoriteit 5%
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);
}
}
Antwoord 5, autoriteit 5%
probeer dit
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();
}
});
}
Antwoord 6, autoriteit 4%
Probeer deze code
Button btn=new Button(this);
btn.setId(btn);
btn.setBackgroundResource(R.drawable.image);
btn.setMinimumHeight(150);
btn.setMinimumWidth(150);
Relativelayout.addView(btn);
Antwoord 7, autoriteit 4%
Controleer dit.
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);
Antwoord 8, autoriteit 4%
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);
Antwoord 9, autoriteit 3%
Probeer deze code. Het zal goed werken..
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);
}
}
Antwoord 10, autoriteit 3%
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");
}
}
});
}
}
Antwoord 11, autoriteit 2%
Probeer de code te volgen.
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);
op deze manier voegt u knoppen toe volgens uw vereisten.
Antwoord 12, autoriteit 2%
Eigenlijk voeg ik aan het xml-layoutbestand alles toe wat gebruikt kan worden! Vervolgens haal ik uit de broncode van de specifieke activiteit het object door zijn id en ik “speel” met de zichtbaarheidsmethode.
Hier is een voorbeeld:
((Spinner)findViewById(R.id.email_spinner)).setVisibility(View.GONE);
Antwoord 13, autoriteit 2%
Ik heb deze (of zeer vergelijkbare) code gebruikt om verschillende TextViews toe te voegen aan een LinearLayout:
// 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);
}
Het belangrijkste verschil tussen deze code en de code van dicklaw795 is dat deze de ID voor elke TextView niet instelt() en opnieuw ophaalt() — ik vond het niet nodig, hoewel ik het later misschien nodig heb om elke knop in een gemeenschappelijke handlerroutine (bijv. een aangeroepen door onClick() voor elke TextView).
Antwoord 14, autoriteit 2%
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();
}
});
Antwoord 15, autoriteit 2%
Als je dynamisch knoppen wilt toevoegen, probeer dan dit:
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);
}
}
Antwoord 16
Je zou een basislay-out voor je knop kunnen maken en alleen dynamisch veranderen wat specifiek is, zoals dit project dat ik heb gemaakt om verschillende oefeningen uit te voeren van een cursus Materiaalontwerp die ik volg:
In dit voorbeeld gebruik ik een vooraf geconfigureerde 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>
En in de MainActivity
heb ik enkele instanties gemaakt en gewijzigd wat ik nodig heb, zoals de knoptekst en onClick-gebeurtenis:
<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);
}
}
Sorry dat ik te laat ben…
Antwoord 17
Ik moest knoppen nog dynamischer maken, niet alleen tijdens runtime, maar door op een andere knop te drukken. Dus als u op deze knop klikt, worden er dynamisch meer knoppen onder gemaakt. Ik raad aan om een ScrollView op de activiteit te gebruiken of het aantal klikken te beperken – zodat er geen knoppen van het scherm verdwijnen.
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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=".MainActivity">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:layout_editor_absoluteY="675dp">
<LinearLayout
android:id="@+id/layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<Button
android:id="@+id/newItemButton"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Button1" />
</LinearLayout>
</ScrollView>
</androidx.constraintlayout.widget.ConstraintLayout>
MainActivity.java
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
LinearLayout ll = (LinearLayout)findViewById(R.id.layout); //Screen layout
LinearLayout.LayoutParams params = new
LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.WRAP_CONTENT);
final Button newItemButton = findViewById(R.id.newItemButton);
newItemButton.setText("Create new button");
newItemButton.setOnClickListener(new View.OnClickListener() {
int pressCount = 1; //Count how many times button was pressed
public void onClick(View v) {
newItemButton.setText("Button Clicked: "+pressCount);
createButton(pressCount, params, ll); //Click to create new button
pressCount++;
}
});
} //end of onCreate
public void createButton(int id, LinearLayout.LayoutParams inputParams, LinearLayout inputLL) {
Button outButton = new Button(this);
outButton.setId(id);
final int id_ = outButton.getId();
outButton.setText("Button " + id_);
inputLL.addView(outButton, inputParams);
}
}//end of AppCompatActivity
Hiermee krijg je een activiteit met een knop.
Wanneer je op die knop klikt, spawn je een nieuwe knop eronder.
Als je er zoveel spawnt dat ze niet op het scherm passen, zorgt de scrollView daarvoor.
Antwoord 18
In mainactivity.xml
schrijf:
<Button
android:id="@+id/search"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Search"
android:visibility="invisible"/>
In main.java
schrijf:
Button buttonSearch;
buttonSearch = (Button)findViewById(R.id.search);
buttonSearch.setVisibility(View.VISIBLE);