How to add a button dynamically in Android?
How to add a button dynamically 开发者_如何学编程in Android?
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);
Have a look to this example
try this:
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();
}
});
}
Try this:
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);
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);
}
}
try this
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();
}
});
}
Try this code
Button btn=new Button(this);
btn.setId(btn);
btn.setBackgroundResource(R.drawable.image);
btn.setMinimumHeight(150);
btn.setMinimumWidth(150);
Relativelayout.addView(btn);
Check this up.
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);
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);
Try this code. It will work fine..
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);
}
}
Try following 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);
like this you add Buttons as per your requirements.
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");
}
}
});
}
}
Actually I add to the xml layout file anything that could be used! Then from the source code of the specific Activity I get the object by its id and I "play" with the visibility method.
Here is an example:
((Spinner)findViewById(R.id.email_spinner)).setVisibility(View.GONE);
I've used this (or very similar) code to add several TextViews to a 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);
}
The main difference between this and dicklaw795's code is it doesn't set() and re-get() the ID for each TextView--I found it unnecessary, although I may need it to later identify each button in a common handler routine (e.g. one called by onClick() for each TextView).
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();
}
});
If you want to add dynamically buttons try this:
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);
}
}
You could create a base layout for your button and dynamically change only what is specific, like this project I made to run different exercises from a Material Design course I'm taking:
In this example, I use a preconfigured 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>
And in the MainActivity
I created some instances and changed what I need, like the button text and onClick event:
<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 for being late...
I needed to create buttons even more dynamically, not just in runtime but by pressing another button. So clicking this button will dynamically create more buttons under it. I recommend having a ScrollView on the activity or limit the number of clicks - so no buttons go offscreen.
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
This will give you an activity with a button. When you click on that button, you spawn a new button underneath it. If you spawn so many that they do not fit on the screen, the scrollView will take care of that.
In mainactivity.xml
write:
<Button
android:id="@+id/search"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Search"
android:visibility="invisible"/>
In main.java
write:
Button buttonSearch;
buttonSearch = (Button)findViewById(R.id.search);
buttonSearch.setVisibility(View.VISIBLE);
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