使用 JAVA 类在 android 中制作按钮

Question

I m noob to android, I have a simple Question. i have TextView in a RelativeLayout, i want to add a button dynamically just below that TextView which is present in a RelativeLayout, how can i do it ? thanks !

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    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"
    android:background="@mipmap/background"
    >

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:id="@+id/container">

        <android.support.v4.view.ViewPager
            android:id="@+id/screen3"
            android:layout_height="wrap_content"
            android:layout_width="wrap_content"
            >
        </android.support.v4.view.ViewPager>

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            >
        <TextView
            android:paddingTop="30dp"
            android:id="@+id/act3_txt1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textSize="35sp"
            android:textAlignment="center"
            android:textColor="#FFFFFF"
            />
        <ImageView
            android:paddingTop="30dp"
            android:id="@+id/cam_images"
            android:layout_height="250sp"
            android:layout_width="wrap_content"
            android:layout_below="@+id/act3_txt1" />
        <TextView
            android:paddingTop="30dp"
            android:id="@+id/act3_txt2"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/cam_images"
            android:textSize="35sp"
            android:textAlignment="center"
            android:layout_centerInParent="true"
            android:textColor="#FFFFFF"
            android:paddingBottom="20dp"/>

        </RelativeLayout>
    </RelativeLayout>


</RelativeLayout>

Answer 1

1) create a button like this inside onCreate().

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

2) then add it into your layout. before it you have to add id for your layout in which you want to show the button.

RelativeLayout = (RelativeLayout) findViewById(R.id.relativeLayoutID);
layout.addView(myButton);

Answer 2

Inflate the relative layout and the existing textview first

relativeLayout= (RelativeLayout) findViewById(R.id.relativeLayout);
textView= (TextView) findViewById(R.id.tittle);

Prepare layout params and addRule method to put the button below the textview

  RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
            ViewGroup.LayoutParams.WRAP_CONTENT);
    params.addRule(RelativeLayout.BELOW, R.id.tittle);
    Button button=new Button(this);
    button.setLayoutParams(params);
    button.setText("Click Me!");
    relativeLayout.addView(button,1);