Android初级教程_监听EditText输入文字的字数

public void init(){
		chCounterText = (TextView) findViewById(R.id.sdk_status_ch_counter);
		statusEdit = (EditText) findViewById(R.id.sdk_status_edit_text);
		statusEdit.addTextChangedListener(new TextWatcher() {
			@Override
			public void afterTextChanged(Editable s) {
			}

			@Override
			public void beforeTextChanged(CharSequence s, int start, int count,
					int after) {
			}

			@Override
			public void onTextChanged(CharSequence s, int start, int before,
					int count) {
				String content = statusEdit.getText().toString();
				chCounterText.setText(content.length() + "/"
						+ MAX_LENGTH);
			}

		});
    }

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <ScrollView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >  //scrollviwe主要是当输入法启动的时候,让EditText自动自动往上滑.否则输入法可能会把输入框遮住

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:orientation="vertical" >

            <TextView
                android:id="@+id/renren_sdk_status_ch_counter"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:layout_alignParentRight="true"
                android:layout_centerVertical="true"
                android:layout_marginRight="10dip"
                android:layout_marginTop="10dip"
                android:gravity="right"
                android:text="0/20"
                android:textColor="#999999"
                android:textSize="14sp" />

            <EditText
                android:id="@+id/renren_sdk_status_edit_text"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:layout_marginBottom="10dip"
                android:layout_marginLeft="10dip"
                android:layout_marginRight="10dip"
                android:layout_marginTop="3dip"
                android:autoText="true"
                android:capitalize="sentences"
                android:focusable="true"
                android:focusableInTouchMode="true"
                android:freezesText="true"
                android:gravity="top"
                android:inputType="textShortMessage|textAutoCorrect|textCapSentences|textMultiLine"
                android:isScrollContainer="false"
                android:maxLength="20"
                android:minHeight="24dip"
                android:minLines="5"
                android:padding="4dip"
                android:textSize="16sp" >
                <requestFocus />
            </EditText>
        </LinearLayout>
    </ScrollView>
</LinearLayout>