Only allow numbers in I2PTunnel wizard port fields (ticket #1331)

app/src/main/java/net/i2p/android/i2ptunnel/TunnelWizardModel.java

@@ -90,6 +90,7 @@ public class TunnelWizardModel extends AbstractWizardModel {
 
             new SingleTextFieldPage(this, res.getString(R.string.i2ptunnel_wizard_k_target_port))
                 .setDescription(res.getString(R.string.i2ptunnel_wizard_desc_target_port))
+                .setNumeric(true)
                 .setRequired(true)
                 .setEqualCondition(cTunnelType, res.getString(R.string.i2ptunnel_wizard_v_server)),
 
@@ -110,6 +111,7 @@ public class TunnelWizardModel extends AbstractWizardModel {
 
             new SingleTextFieldPage(this, res.getString(R.string.i2ptunnel_wizard_k_binding_port))
                 .setDescription(res.getString(R.string.i2ptunnel_wizard_k_binding_port))
+                .setNumeric(true)
                 .setRequired(true)
                 .setEqualCondition(cTunnelType, res.getString(R.string.i2ptunnel_wizard_v_client))
                 .setEqualCondition(cServerType, res.getString(R.string.i2ptunnel_type_httpbidirserver)),

app/src/main/java/net/i2p/android/wizard/model/SingleTextFieldPage.java

@@ -30,6 +30,7 @@ public class SingleTextFieldPage extends Page {
     // The null is checked in SingleTextFieldFragment
     protected String mDef = null;
     protected String mDesc = "";
+    protected boolean mNumeric = false;
 
     public SingleTextFieldPage(ModelCallbacks callbacks, String title) {
         super(callbacks, title);
@@ -68,6 +69,15 @@ public class SingleTextFieldPage extends Page {
         return mDesc;
     }
 
+    public SingleTextFieldPage setNumeric(boolean numeric) {
+        mNumeric = numeric;
+        return this;
+    }
+
+    public boolean getNumeric() {
+        return mNumeric;
+    }
+
     // Override these in subclasses to add content verification.
 
     public boolean isValid() {

app/src/main/java/net/i2p/android/wizard/ui/SingleTextFieldFragment.java

@@ -25,6 +25,7 @@ import android.content.Context;
 import android.os.Bundle;
 import android.support.v4.app.Fragment;
 import android.text.Editable;
+import android.text.InputType;
 import android.text.TextWatcher;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -71,6 +72,8 @@ public class SingleTextFieldFragment extends Fragment {
 
         mFieldView = ((TextView) rootView.findViewById(R.id.wizard_text_field));
         mFieldView.setHint(mPage.getTitle());
+        if (mPage.getNumeric())
+            mFieldView.setInputType(InputType.TYPE_CLASS_NUMBER);
         if (mPage.getData().getString(Page.SIMPLE_DATA_KEY) != null)
             mFieldView.setText(mPage.getData().getString(Page.SIMPLE_DATA_KEY));
         else if (mPage.getDefault() != null) {