Java 如何检查一行或多行是否已从TextView中删除?
我正在制作一个ide,并使用TextView根据EditText的行数显示行号。我有添加新行的功能,但如何检查是否删除了一行并减少TextView的行数Java 如何检查一行或多行是否已从TextView中删除?,java,android,textview,Java,Android,Textview,我正在制作一个ide,并使用TextView根据EditText的行数显示行号。我有添加新行的功能,但如何检查是否删除了一行并减少TextView的行数 et.setOnKeyListener(new OnKeyListener() { @Override public boolean onKey(View v, int keyCode, KeyEvent event) { if ((event.getAction() == KeyEvent.ACTION_DOWN) &&am
et.setOnKeyListener(new OnKeyListener() {
@Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
if ((event.getAction() == KeyEvent.ACTION_DOWN) &&
(keyCode == KeyEvent.KEYCODE_ENTER)) {
lines++;
lineNumbers.append(lines+"\n");
}
return false;
}
})) 这就成功了
private void openFile(final File aFile) {
String nullChk = et.getText().toString();
exists = true;
if (!changed || nullChk.matches("")) {
try {
currentFile = aFile;
et.setText(new Scanner(currentFile).useDelimiter("\\Z").next());
lineNumbers.setText("");
lines = 1;
for (int i = 1; i < et.getLineCount(); i++) {
lineNumbers.append(lines + "\n");
lines++;
...
}
et.setOnKeyListener(new OnKeyListener() {
@Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
if ((event.getAction() == KeyEvent.ACTION_DOWN)
&& (keyCode == KeyEvent.KEYCODE_ENTER)) {
lines++;
lineNumbers.append(lines + "\n");
}
if ((event.getAction() == KeyEvent.ACTION_DOWN)
&& (keyCode == KeyEvent.KEYCODE_DEL)) {
lineNumbers.setText("");
lines = 0;
for (int i = 1; i < et.getLineCount(); i++) {
lines++;
lineNumbers.append(lines + "\n");
}
}
return false;
}
});
private void openFile(最终文件aFile){
字符串nullChk=et.getText().toString();
存在=真;
如果(!changed | | nullChk.matches(“”){
试一试{
currentFile=aFile;
et.setText(新扫描仪(当前文件).useDelimiter(“\\Z”).next();
linenumber.setText(“”);
直线=1;
对于(int i=1;i