Fix UI for Android TTS Engine. (#1735)

Set max number of lines of the input text field so that
the buttons are still visible when the input text is long.

Author: csukuangfj

android/SherpaOnnxTtsEngine/app/src/main/java/com/k2fsa/sherpa/onnx/tts/engine/MainActivity.kt

@@ -22,7 +22,9 @@ import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.wrapContentHeight
+import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.foundation.verticalScroll
 import androidx.compose.material3.Button
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.MaterialTheme
@@ -109,6 +111,7 @@ class MainActivity : ComponentActivity() {
                                 var rtfText by remember {
                                     mutableStateOf("")
                                 }
+                                val scrollState = rememberScrollState(0)
 
                                 val numSpeakers = TtsEngine.tts!!.numSpeakers()
                                 if (numSpeakers > 1) {
@@ -142,9 +145,11 @@ class MainActivity : ComponentActivity() {
                                     value = testText,
                                     onValueChange = { testText = it },
                                     label = { Text("Please input your text here") },
+                                    maxLines = 10,
                                     modifier = Modifier
                                         .fillMaxWidth()
                                         .padding(bottom = 16.dp)
+                                        .verticalScroll(scrollState)
                                         .wrapContentHeight(),
                                     singleLine = false,
                                 )