Add button dynamically to fingerpaint android api demos

Now i would like to add button dynamically in FingerPaint api demos. But the problem is that i ain't familiar with creating layo开发者_运维百科ut dynamically in java file. does somebody know how can i implement this class to add buttons in title bar? Any code samples would be appreciate.

Explanation:

1) Get a reference to the layout container where to insert the dynamic gui component. If the container was created dynamically, you already have a reference to it. If it comes from a xml layout, you can get a reference with findViewById.

2) Create a dynamic component. You need to pass a context to the constructor: Use this.

3) Set the created component properties.

4) Use container.addView(component) to add the component dynamically to the container.

Step by step demo:

1) Use the project assistant to create a new Android project with default options, package test.test, and a Main activity.

2) Edit the res/layout/main.xml file as follows.

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:orientation="vertical"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        >
        <LinearLayout 
            android:orientation="vertical"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:id="@+id/layoutId"
            >
        </LinearLayout>
    </LinearLayout>

3) Edit the src/test.test/Main.javafile as follows.

    package test.test;

    import android.app.Activity;
    import android.os.Bundle;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.LinearLayout;
    import android.widget.Toast;

    public class Main extends Activity {
        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            addDynamicButton();
        }

        /**
         * Adds a dynamic button.
         */
        private void addDynamicButton() {
            // creates a button dynamically
            Button btn = new Button(this);
            // sets button properties
            btn.setText("I'm dynamic. Please click me.");
            btn.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(View v) {
                    Toast toast = Toast.makeText(Main.this, "Yo!", Toast.LENGTH_LONG);
                    toast.show();
                }
            });
            // retrieve a reference to the container layout
            LinearLayout container = (LinearLayout)findViewById(R.id.layoutId);
            // adds dynamic button to the GUI
            container.addView(btn);
        }
    }

4) Compile and run as an Android application. Now you know how it works and you can use this technique to add any kind of component to any layout container.