Making TextView scrollable on Android
I am displaying text in a textview that appears to be too long to fit into one screen. I need to make my TextView scrollable. How can I do that?
Here is the code:
final TextView tv = new TextView(this);
tv.setBackgroundResource(R.drawable.splash);
tv.setTypeface(face);
tv.setTextSize(18);
tv.setTextColor(R.color.BROWN);
tv.setGravity(Gravity.CENTER_VERTICAL| Gravity.CENTER_HORIZONTAL);
tv.setOnTouchListener(new OnTouchListener() {
public boolean onTouch(View v, MotionEvent e) {
Random r = new Random();
int i = r.nextInt(101);
if (e.getAction() == e.ACTION_DOWN) {
tv.setText(tips[i]);
tv.setBackgroundResource(R.drawable.inner);
}
return true;
}
});
setContentView(tv);
You don't need to use a ScrollView actually.
Just set the
android:maxLines = "AN_INTEGER"
android:scrollbars = "vertical"
properties of your TextView in your layout's xml file.
Then use:
yourTextView.setMovementMethod(new ScrollingMovementMethod());
in your code.
Bingo, it scrolls!
This is how I did it purely in XML:
<?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">
<ScrollView
android:id="@+id/SCROLLER_ID"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:scrollbars="vertical"
android:fillViewport="true">
<TextView
android:id="@+id/TEXT_STATUS_ID"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1.0"/>
</ScrollView>
</LinearLayout>
NOTES:
android:fillViewport="true" combined with android:layout_weight="1.0" will make the textview take up all available space.
When defining the Scrollview, DO NOT specify android:layout_height="fill_parent" otherwise the scrollview doesn't work! (this has caused me to waste an hour just now! FFS).
PRO TIP:
To programmatically scroll to the bottom after appending text, use this:
mTextStatus = (TextView) findViewById(R.id.TEXT_STATUS_ID);
mScrollView = (ScrollView) findViewById(R.id.SCROLLER_ID);
private void scrollToBottom()
{
mScrollView.post(new Runnable()
{
public void run()
{
mScrollView.smoothScrollTo(0, mTextStatus.getBottom());
}
});
}
All that is really necessary is the setMovementMethod(). Here's an example using a LinearLayout.
File main.xml
<?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"
>
<TextView
android:id="@+id/tv1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="@string/hello"
/>
</LinearLayout>
File WordExtractTest.java
public class WordExtractTest extends Activity {
TextView tv1;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
tv1 = (TextView)findViewById(R.id.tv1);
loadDoc();
}
private void loadDoc() {
String s = "";
for(int x=0; x<=100; x++) {
s += "Line: " + String.valueOf(x) + "n";
}
tv1.setMovementMethod(new ScrollingMovementMethod());
tv1.setText(s);
}
}