ScrollViewDemo

main.xml

宣告一個Scroll view...  然後裡面用一個linear layout

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<LinearLayout 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:orientation="vertical"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    android:paddingBottom="@dimen/activity_vertical_margin"    tools:context=".MainActivity">

    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="horizontal"   // 水平方向        android:padding="6dp">

        <Button            android:id="@+id/btAdd"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:onClick="onAddClick"            android:text="@string/text_btAdd" />

        <TextView            android:id="@+id/tvCount"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_marginLeft="50dp" />
    </LinearLayout>

    <ScrollView        android:id="@+id/scrollView"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:padding="6dp">

        <LinearLayout            android:id="@+id/linearLayout"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:padding="6dp"            android:orientation="vertical" />

    </ScrollView>
</LinearLayout>

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main.java

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public class MainActivity extends AppCompatActivity {

    private TextView tvCount;
    private ScrollView scrollView;
    private LinearLayout linearLayout;
    private int count = 0;
    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViews();
        tvCount.setText(String.valueOf(count));   //  初始值
    }

    private void findViews() {
        tvCount = (TextView) findViewById(R.id.tvCount);
        scrollView = (ScrollView) findViewById(R.id.scrollView);
        linearLayout = (LinearLayout) findViewById(R.id.linearLayout);  // scrollview 裡面的linear layout
    }


    public void onAddClick(View view) {
        count++;
        tvCount.setText(String.valueOf(count));  //  更新目前的 count

        TextView textView = new TextView(this);    // 宣告並初始一個Textview
        textView.setText(String.valueOf(count));    //  textview set text
        linearLayout.addView(textView);            //   增加到linearlayout

        scrollView.post(new Runnable() {               //  更新scroll view.. 使用 Runnable
            @Override            public void run() {
                scrollView.fullScroll(View.FOCUS_DOWN);
            }
        });
    }
}